MPs have called for tougher measures to protect passengers and local communities before plans to expand Heathrow Airport are approved.
The Transport Committee said a night flight ban of six-and-a-half hours should to be extended to seven hours.
The MPs also want further evidence that landing charges will not be raised to pay for a third runway.
If these and other concerns are addressed, the MPs said Parliament should approve Heathrow expansion.
A Department for Transport spokeswoman said: “Expansion will only proceed if it meets strict environmental obligations and offers a world-class package of compensation and mitigations for local communities.”
What does the report say?
The report says government should press ahead with its Airports National Policy Statement, which if approved by Parliament would effectively give permission for planning for Heathrow’s expansion to proceed.
However, as well as a more stringent night flight ban, it says environmental and regional connectivity concerns must also be addressed.
“Thousands of people across London could be exposed to worse levels of noise, air quality and traffic congestion – there must be sufficient measures to protect or compensate them,” said Lilian Greenwood, chair of the Transport Committee.
“The draft [statement] does not guarantee that passengers will be protected from the cost risks associated with the scheme. The secretary of state must set out how airport charges will be held down,” she said.
What does Heathrow say?
Heathrow welcomed the MPs’ report and called for Parliament to allow the project to move into the planning phase.
“We are also clear that we will deliver an expanded Heathrow that is sustainable, affordable and financeable,” a spokesperson said.
The CBI has also urged government to finalise the airport strategy: “With the new global links that it will bring, and the opportunity to unlock jobs right across the UK, getting on with building the third runway at Heathrow is a vital part of this equation.”
What do the critics say?
Critics have long argued that a new runway at Heathrow would disrupt local communities.
John Stewart, chair of campaigning group Hacan, estimates the number of flights from Heathrow will increase from about 476,000 to more than 700,000 flights a year.
“We are disappointed that they haven’t said no to a third runway… but having said that we do welcome the conditions on air pollution and noise that they are recommending – in particular the seven hour night ban,” he told the BBC.
IAG, which owns British Airways and Iberia and is the biggest user of the airport, has criticised the proposed cost of Heathrow’s expansion plans as “exorbitant and unacceptably vague”.
Willie Walsh, IAG chief executive, said: “It’s critical the National Policy Statement includes a detailed cost breakdown with the condition that airport charges be held flat in real terms, before parliament votes on it.”
When will there be an agreement on Heathrow expansion?
MPs are expected to vote on the airports policy statement in the first half of this year.
If it is approved, the proposals will enter an official planning process.
Heathrow hopes to start building a new runway in early 2021, with completion by the end of 2025.
Analysis: Victoria Fritz, BBC transport correspondent
In 2015 the Airports Commission concluded that a proposal for a northwest runway at Heathrow was the best option for airport expansion in the South East.
With just a few months to go before a parliamentary vote to rubber stamp the proposal, the Transport Committee has urged the government to go back to the drawing board.
The detail on projected costs and benefits is not sufficiently granular, the committee says, for the current proposal to avoid legal challenge. In addition, the MPs say not enough safeguards are in place to ensure that passengers and airlines do not foot the bill through higher airport charges.
Getting this document, called the National Policy Statement, right matters because it is what the Transport Secretary will use to judge Heathrow’s planning application.
Given the scope of the changes that have been recommended, it appears we are still some way from planning permission being granted, let alone seeing the bulldozers move in.